PRACTICAL EXPERIENCE

The REVEL-PEX system is incredibly willing to operate faultlessly in practice. In case that the system does not work as assumed check temperatures of supply and return lines for misconnection. Another very common fault is overloading of the branch – check according to the chart “J”. If any of the above faults occurs, the situation can be suitably remedied by installation of a powerful pump (for example well-priced WILO RS30/100). When connecting bodies, it is recommended to proceed by supply lines first and then by return pipes to eliminate pipe crossing and wrong connection.  When leading ascending pipes always mark the supply and return pipes. After pressing the fitting can be rotated. This has no effect on the tightness of connection and similar effect as with lip seal is concerned. Speed of the assembly is almost unbelievable and material handling is easy. According to the relevant standard, when installing pipes the temperature should not drop below +5 °C. However, many companies work at temperatures below -5 °C. Owing to the frost resistance of the material no damage of distributions occurs, however, increased caution is necessary. It is recommended to pre-heat the material in a small heated room. Equipment demands and training requirements of the work group are minimal compared with traditional steel piping. Besides the mentioned special tools the work group (mostly two-membered) will need a cutting machine for radiator connectors and scissors for plastic materials, also offered by our company. There is no need to anchor piping to the foundation. For possible attachment of piping to the foundation, e.g. in case of double floors by reason of noise, it is necessary to use plastic dowels with a stripe or tree-like anchors, and plates or any other sharp-edged material shall be avoided. When passing through the dilatation zone of building structures it is necessary to apply the PE cover with 0,25 m overlap on each side (this also applies for room-to-room and floor-to-wall joints). Wall-mounted pipes PEX (metal-plastic pipes always) should be placed into polyethylene covers and grooves 100 mm deep (the cover cannot be connected in corners, but must pass over). Covering of the PEX pipes laid in concrete without covers should match the pipe dimension, i.e. for the pipe diameter of 20 mm the cover should be at least 20 mm above the upper edge of the pipe profile, etc. Passages through doors should be uniform in order to avoid damage of distributions by drilling of thresholds. Special attention is also required in case of toilet bowls, washbowl feet, bar seats, etc. Connections of size 23 shall be fixed in concrete or otherwise to avoid possible mechanical loading resulting from length variations of pipes not fixed in concrete. Systems without sloping are deaerated for much longer time than in the case of classic pipe systems and sometimes the pressure drop in the system requiring water addition is so steady that it creates the impression of water leakage. This is caused by additional shape modification of the pipes due to temperature and pressure. In case of larger systems it is recommended to use automatic balancing and refilling equipment. For smaller systems always use automatic refilling fitting ADA (RL374). In addition to the reduction and return valves it also includes a control manometer. The fitting is left slightly open for a couple of months and then it is only used for pre-season refilling. It is not recommended to install the PE-X material on the surface without covering. It is not recommended to use the PE-X material wherever sufficient protection against overheating is not ensured for solid fuel sources (including fireplace inserts). The material is able to resist hot water of 110 °C in the short term, but if vapour penetrates into the system (e.g. in case of pressure drop in the system) the PE-X material net structure melts at the point of its condensation. Paradoxically, this point may be located several meters from the source and the safety valve does not solve it. The best solution seems to be inclusion of the accumulation vessel, the use of open expansion or the placement of UPS source to ensure several hours of pump operation in case of electrical network failure. In any case it is recommended to furnish the solid fuel sources room with steel or copper elements and to use the PE-X material in walls or floors only.
The practice has not proven omission of correct method for filling floor or wall-mounted systems nor gradual heating of floor by individual grades and days proved substantiated. Therefore we recommend the following method: close distributor inlet and outlet, close all loop valves, secure water inlet to the collector discharge valve, open inlet and possibly regulation (reverse) valve of one circuit, wait until delivered quantity of water flows out of the distributor discharge valve (without air bubbles), close this loop and proceed in the same way with other ones, after all circuits are filled, open all valves, start the heat source without limitation.